html, body {margin: 0; padding: 0; height: 100%;}
body {
  font-size: 15px;
  line-height: 1.95em;
  font-family: "Source Sans Pro", Helvetica, Arial, Sans-Serif;
  display: block;
  background: #FFF;
  overflow-y: scroll;
}

.bovenkantHolder {background-color: #eeeeee; position: relative; width: 100%;}
.bovenkantHolder .bovenkantInhoud {
  color: #666;
  font-size: 23px;
  margin: 0 auto;
  padding: 15px 30px 20px 30px;
  position: relative;
  max-width: 1200px;
  box-sizing: border-box;
  text-align: center;
}

a.knop {
  border: 1px solid #000; 
  background-color: transparent; 
  text-decoration: none; 
  color: #000; 
  padding: 15px 20px; 
  font-size: 15px; 
  transition: .3s all ease;
}
a.knop:hover {background-color: #000; color: #FFF;}